Latest news with #DESILegacySurvey
Yahoo
18-04-2025
- Science
- Yahoo
'New' Tatooine-Like Exoplanet Appears to Orbit 2 Failed Stars
Scientists have found evidence of a Tatooine-like exoplanet that orbits two stars instead of one. Unlike the other 15 circumbinary planets to mimic the orbit of Star Wars' most famous planet, though, this one appears to circle failed stars. Astronomers not involved in the research consider it "some of the most direct evidence yet" of this unique type of system. The planet in question is 2M1510 (AB) b, and while it hasn't yet been observed directly, data strongly suggests that it exists. Its discovery follows that of two strange stars 120 light-years from Earth: a pair of brown dwarfs, otherwise known as failed stars. While one of the brown dwarfs had been on researchers' radar since 2018, it was only found last year to have been two failed stars, which were too light to ignite. The 45 million-year-old brown dwarfs orbit each other every 12 days, circling a small, proper star just 18 light-years away. But what orbits them? Using the Very Large Telescope (VLT) in Chile, researchers in the United Kingdom and Portugal found that both brown dwarfs orbit in opposition to their own orbital motion. Thanks to new data analysis methods developed by astronomer Lalitha Sairam when she was at the University of Birmingham, the team knew their findings weren't a fluke: Sairam's methods had improved the precision of their observations by a factor of 30. That meant the odd pattern could only be explained by gravitational bumps from another object, which would need to orbit the failed stars at roughly a 90-degree angle. A visible light image of the two brown dwarfs locked in a binary system. Credit: DESI Legacy Survey/D. Lang (Perimeter Institute) "We had hints that planets on perpendicular orbits around binary stars could exist, but until now we lacked clear evidence of this type of polar planet," PhD student and lead study author Thomas Baycroft said. "We reviewed all possible scenarios, and the only consistent with the data is if a planet is on a polar orbit about this binary." Baycroft and his colleagues consider their discovery "serendipitous," as they'd been using the VLT to study the binary brown dwarf system in general, not to find a new planet. "It is a big surprise and shows what is possible in the fascinating universe we inhabit, where a planet can affect the orbits of its two stars, creating a delicate celestial dance," Baycroft said.
Yahoo
08-02-2025
- Science
- Yahoo
'Bullseye' Galaxy Captured in Spellbinding Hubble Image
Tens of millions of years ago, a humble blue dwarf galaxy plunged through space, leaving hoops of gas and dust in its wake. Now those hoops surround a "new" galaxy. Thanks to the Hubble Space Telescope, researchers at Yale University have discovered the freshly-named "bullseye galaxy," which features nine sparkling rings and more than doubles the size of our Milky Way. The bullseye galaxy's official name is LEDA 1313424, and it's an eye-watering 567 million light-years away from Earth. Yale astronomer Imad Pasha was reviewing ground-based imaging data from the DESI Legacy Survey when he spotted "a galaxy with several clear rings," which he "had to stop to investigate." Using Hubble's trusty ACS (Advanced Camera for Surveys) system, he and his colleagues pursued the above image of LEDA 1313424, which fully revealed the galaxy's bullseye shape. Hubble's image allowed Pasha to inspect eight of the bullseye's rings—more starry hoops than have been detected by any telescope in any galaxy, according to NASA. But faint patches of emission 70 kiloparsecs (228,309 light-years) away from the galaxy's center led the team to believe another ring swirled just out of sight. They used the Keck Cosmic Web Imager (KCWI) at Hawaii's W. M. Keck Observatory to capture the galaxy's spectroscopic data, and sure enough, a ninth ring lurked at the bullseye's outer edge. Artist's concept showing the distribution of LEDA 1313424's rings. Credit: NASA, ESA, Ralf Crawford (STScI) These rings formed in much the same way as ripples in a pond. When you drop a pebble into a body of water, small, ring-shaped waves ripple outward, gradually becoming larger and more spaced out. Pasha and his colleagues were delighted to find that, mathematically, the bullseye galaxy's rings follow the same pattern. When a blue dwarf galaxy passed through what's now the bullseye's center 50 million years ago, it triggered ripples of stellar material. While the two oldest rings spread outward and grew further apart, the newest rings continued to hug the galaxy's center more closely. That blue dwarf galaxy is still in the bullseye's vicinity—in fact, it's attached to the bullseye by a thin thread of gas roughly 130,000 light-years long. In the image at the top of this page, you can see it to the bullseye galaxy's immediate left. "We're catching the Bullseye at a very special moment in time," Pieter van Dokkum, astrophysicist and study co-author, told NASA. "There's a very narrow window after the impact when a galaxy like this would have so many rings."
